Object responsive control system for a work machine

CROSS-REFERENCE TO RELATED APPLICATIONS

N/A

FIELD OF THE DISCLOSURE

The present disclosure relates to an object responsive control system for a work machine, and more particularly activating an object response when an undesirable object is sensed.

BACKGROUND

Work machine often operate in harsh environments, one of which may include sharp and jagged volcanic rock. Some materials (e.g. volcanic rock) may severely damage the ground engaging supports of a work machine and its frame while the work machine is propelling forwards. However, this damage only occurs when the attachment is in a carrying or dumping position where the linkage connecting the attachment to the work machine, the attachment, and the load pile obstructs the operator's view of the travel path. The following disclosure helps address the issues of potential damage to the work machine and improving its safety during operation in such environments.

SUMMARY

This summary is provided to introduce a selection of concepts that are further described below in the detailed description and accompanying drawings. This summary is not intended to identify key or essential features of the appended claims, nor is it intended to be used as an aid in determining the scope of the appended claims.

The present disclosure includes an object responsive control system which allows the control system for a work machine to activate an object response when an undesirable object is sensed in a travel path of the work machine, and when the attachment of the work machine meets certain positional requirements. More specifically, an object response is activated when the attachment has attained an elevational position above a predetermined threshold.

According to an aspect of the present disclosure, the following is an object responsive control system for a work machine that has a frame, a longitudinal axis, ground engaging supports to support the frame on a geographic surface, and a prime mover mounted on the work machine where the prime mover is drivingly coupled to the ground engaging supports. The prime mover propels the work machine over the geographic surface.

The control system comprises a boom pivotally coupled to the frame; an attachment pivotally coupled to the boom, the attachment extending in a direction transverse to the longitudinal axis of the work machine; an object sensor; a boom sensor adapted for delivering a boom position signal; an attachment sensor adapted for delivering an attachment position signal; and a controller. The object sensor is adapted for sensing the presence of an undesirable object located on the geographic surface in a travel path of the work machine, and further adapted to deliver an object signal upon sensing the undesirable object on the geographical surface. The controller is adapted for receiving the boom position signal, receiving the attachment position signal, calculating an attachment elevation position based on the boom position signal and the attachment position signal; and further adapted to activate an object response upon calculating an attachment elevation position above a predetermined threshold and receiving an object signal. Calculating an elevational position may further comprise a recognition of a type of the attachment.

The system further comprises an operator station. The operator station is supported by the frame, and defines a location for an operator to operate the work machine while facing the attachment. The predetermined threshold is defined by the elevational level where the operator's view of the travel path is at least partially obstructed by the attachment.

The attachment may either be a bucket, a fork, or a spear.

The object sensor may be further adapted to activate a secondary object signal upon sensing the undesirable object on the geographical surface in the travel path of the work machine and elevationally below the attachment of the work machine.

The object sensor may be further adapted for sensing the presence of an undesirable object from an operator's point of view through a windshield of the operator's station within a field of view of the windshield.

The object sensor may comprise of at least one of a laser sensor, a radar sensor, an infrared sensor, an acoustic sensor, a light sensor, a color sensor, and a camera.

The controller is further adapted to deactivate the object response upon calculating an attachment elevation position below the predetermined threshold.

The object response can be at least one of an audible alarm, a visual indicator, an automated reduction in propel speed of the work machine, or an automated electro-hydraulic braking of the ground-engaging supports.

According to an aspect of the present disclosure, a method for providing an object responsive control for a work machine may include one or more of the following steps: propelling the work machine in a travel path on the geographic surface; sensing an undesirable object located on the geographic surface in the travel path of the work machine; delivering an object signal upon sensing the undesirable object on the geographical surface in the travel path of the work machine; delivering a boom position signal; delivering an attachment position signal; calculating an attachment elevation position based on the boom position signal and the attachment position signal; and activating an object response upon calculating an attachment elevation position above a predetermined threshold and receiving an object signal. The predetermined threshold may define an attachment elevation level where the operator's view of the travel path is at least partially obstructed by an attachment when operating the work machine from an operator's station. The operator's view of the travel path is defined by an operator's point of view through a windshield of the operator station within a field of view of the windshield. The attachment may comprise of a bucket, a fork, or a spear. Calculation of the elevational position may further comprise a recognition of a type of attachment.

The method may further comprise deactivating the object response upon calculating an attachment elevation position below the predetermined threshold.

The method may further comprise activating a second object response upon sensing the undesirable object on the geographical surface in the travel path of the work machine and elevationally below the attachment of the work machine. The object response is at least one of an audible alarm, a visual indicator, an automated reduction in propel speed, or an automated electro-hydraulic braking of the ground-engaging supports.

These and other features will become apparent from the following detailed description and accompanying drawings, wherein various features are shown and described by way of illustration. The present disclosure is capable of other and different configurations and its several details are capable of modification in various other respects, all without departing from the scope of the present disclosure. Accordingly, the detailed description and accompanying drawings are to be regarded as illustrative in nature and not as restrictive or limiting.

BRIEF DESCRIPTION OF THE DRAWINGS

The detailed description of the drawings refers to the accompanying figures in which:

<figref idref="DRAWINGS">FIG. 1A</figref> is a schematic side view of an embodiment of a work machine with a boom pivotally coupled to the frame, and an attachment pivotally coupled to the boom in a loading position;

<figref idref="DRAWINGS">FIG. 1B</figref> is a schematic side view of the embodiment in <b>1</b>A in a first carrying position;

<figref idref="DRAWINGS">FIG. 1C</figref> is a schematic side view of the embodiment in <b>1</b>A in a second carrying position;

<figref idref="DRAWINGS">FIG. 2</figref> is a partial top view of the embodiment in <figref idref="DRAWINGS">FIG. 1A</figref>;

<figref idref="DRAWINGS">FIG. 3</figref> is a block diagram of the object responsive control system;

<figref idref="DRAWINGS">FIG. 4A</figref> is a schematic side view of a type of attachment, the bucket;

<figref idref="DRAWINGS">FIG. 4B</figref> is a schematic side view of a type of attachment, the spear;

<figref idref="DRAWINGS">FIG. 4C</figref> is a schematic side view of a type of attachment, the fork;

<figref idref="DRAWINGS">FIG. 5</figref> is a flowchart of a method for providing an object responsive control for a work machine.

DETAILED DESCRIPTION

The embodiments disclosed in the above drawings and the following detailed description are not intended to be exhaustive or to limit the disclosure to these embodiments. Rather, there are several variations and modifications which may be made without departing from the scope of the present disclosure.

<figref idref="DRAWINGS">FIGS. 1A through 1C</figref> illustrate a work machine <b>10</b> with an object responsive control system <b>20</b> (shown in <figref idref="DRAWINGS">FIG. 3</figref>) adapted to activate an object response upon calculating an attachment elevation position <b>30</b> above a predetermined threshold and upon receiving an object signal <b>40</b>. The particular work machine <b>10</b> shown in <figref idref="DRAWINGS">FIGS. 1A through 1C</figref> is a loader. However, it is to be noted that other work machines, such as dozers, skid steers, crawlers, backhoes and the like may be equivalent and within the scope of this disclosure. The work machine <b>10</b> has a frame <b>50</b>, a longitudinal axis <b>60</b> extending along the length of the frame <b>50</b>, and ground engaging supports <b>70</b> to support the frame <b>50</b> on a geographic surface <b>80</b>. The ground engaging supports <b>70</b> may include tracks, wheels, or other supports that assist in moving the work machine. A prime mover (not shown), such as an internal combustion engine, is mounted on the frame <b>50</b> and is drivingly coupled to the ground engaging supports <b>70</b> through conventional means, such as mechanical fluid, or a hydrostatic transmission (not shown). The prime mover mobilizes the ground engaging supports <b>70</b> and propels the work machine <b>10</b> over the geographic surface <b>80</b>.

As shown in <figref idref="DRAWINGS">FIG. 3</figref>, the system <b>20</b> comprises a boom <b>90</b> pivotally coupled to the frame <b>50</b> (<figref idref="DRAWINGS">FIGS. 1A-1C</figref>), an attachment <b>100</b> pivotally coupled to the boom <b>90</b> (<figref idref="DRAWINGS">FIGS. 1A-1C</figref>), an object sensor (<b>110</b>A or <b>110</b>B), a boom sensor <b>120</b>, an attachment sensor <b>130</b>, and a controller <b>140</b>. Now turning to <figref idref="DRAWINGS">FIGS. 1A-1C</figref>, the boom <b>90</b> may comprise of a forwardly projecting boom arm <b>150</b> pivotally mounted on the frame <b>50</b> to pivot about an axis <b>160</b>, and an attachment <b>100</b> (e.g. a bucket) pivotally mounted at the outer end of the boom arm for pivotal movement about an axis <b>180</b>. The attachment <b>100</b> extends in a direction transverse to the longitudinal axis <b>60</b> of the work machine <b>10</b>.

As shown in <figref idref="DRAWINGS">FIG. 3</figref>, the boom sensor <b>120</b> is adapted for delivering a boom position signal <b>125</b>. The attachment sensor <b>130</b> is adapted for delivering an attachment position signal <b>135</b>. The controller <b>140</b> is adapted for receiving the boom position signal <b>125</b>, receiving the attachment position signal <b>135</b>, and calculating an attachment elevational position <b>30</b> (shown in <figref idref="DRAWINGS">FIGS. 1A-1C</figref>) based on the boom position signal <b>125</b> and the attachment position signal <b>135</b>. The controller <b>140</b> may be further adapted to activate an object response <b>145</b> upon calculating an attachment elevational position <b>30</b> above a predetermined threshold and receiving an object signal <b>40</b>. The attachment <b>100</b> may be either a bucket <b>190</b>, a fork <b>200</b>, a spear <b>210</b>, or a similar attachment as shown in <figref idref="DRAWINGS">FIGS. 4A-4C</figref>. Attachment elevational position <b>30</b> may be calculated relative to the frame <b>50</b> of the work machine. Attachment elevational position <b>30</b> may further be calculated as the elevational height from the bottom surface of the attachment to a distance where the ground engaging supports <b>70</b> engage the geographic surface <b>80</b>.

Now referring to <figref idref="DRAWINGS">FIGS. 1A-1C, and 2</figref>, in one embodiment of the work machine, a T-bar linkage <b>250</b> may interconnect the frame <b>50</b> with the attachment <b>100</b> and the boom arms <b>150</b>. The linkage may comprise a unitary cross-shaped bellcrank <b>260</b> which comprises a forward arm <b>220</b>, a rearward arm <b>230</b>, and lateral arms <b>240</b>. <figref idref="DRAWINGS">FIG. 2</figref> shows the cross-shaped configuration of the bellcrank <b>260</b>. The forward arm <b>220</b> of the bellcrank <b>260</b> is pivotally coupled to the attachment <b>100</b> to pivot about an axis <b>180</b>. Rearward arm <b>230</b> is pivotally coupled to the frame <b>50</b> with an intermediate hydraulic cylinder <b>270</b>. The head end <b>280</b> of intermediate hydraulic cylinder <b>270</b> is connected to the frame <b>50</b> to pivot about an axis <b>285</b>, while the rod <b>290</b> is pivotally connected to bellcrank <b>260</b> to pivot about axis <b>295</b>.

The boom <b>90</b> is raised and lowered by a pair of hydraulic cylinders <b>340</b>, one on each side of the work machine <b>10</b>. The head ends of hydraulic cylinders <b>340</b> are pivotally connected to the frame <b>50</b> to pivot about an axis <b>160</b>. The rod ends of hydraulic cylinders <b>340</b> are pivotally connected to boom arms <b>150</b> to pivot about axis <b>410</b>.

In operation the boom <b>90</b> may be moved from the loading position as illustrated in <figref idref="DRAWINGS">FIG. 1A</figref> to the carrying position as shown in <figref idref="DRAWINGS">FIG. 1B</figref> or <figref idref="DRAWINGS">FIG. 1C</figref>. This may be accomplished by extending the hydraulic cylinders <b>340</b> and simultaneously rolling back the attachment <b>100</b> to the carry position by retracting the intermediate hydraulic cylinder <b>270</b>. In the carry position, the load in the implement may be transported to another location where it is to be discharged. In this elevated carry position, the operator's view <b>300</b> (designated by the dotted line) of the travel path <b>310</b> from the operator station <b>320</b> is typically at least partially obstructed by the attachment <b>100</b> and possibly including the load (not shown), while the operator is facing the attachment <b>100</b>. The operator's view <b>300</b> may be defined as the operator's point of view of the travel path <b>310</b> through a windshield <b>330</b> of the operator's station <b>320</b>, and within a field of view of the windshield <b>330</b>. The work machine may encounter obstacles (e.g. large hard rocks, shot rock, stones found in rock quarries) in the field when transporting loads in the carrying position that may cause irreparable damage to its ground engaging supports <b>70</b> or frame <b>50</b>. Whereas, in the loading position as shown in <figref idref="DRAWINGS">FIG. 1A</figref>, the attachment simply “scoops up” the obstacles with the attachment <b>100</b>. The object responsive control system <b>20</b> addresses this issue with a controller <b>140</b> adapted to activate an object response upon calculating an attachment elevational position <b>30</b> above a predetermined threshold and encountering an undesirable object, activating the object response only when this minimum predetermined threshold is met. This predetermined threshold may be defined by an attachment elevational level position <b>30</b> where the operator's view <b>300</b> of the travel path <b>310</b> is at least partially obstructed by the attachment <b>100</b> (e.g. in carrying positions as shown in <figref idref="DRAWINGS">FIGS. 1B and 1C</figref>).

As previously noted, the attachment elevational position <b>30</b> may be calculated based on a boom position signal <b>125</b> from at least one boom sensor <b>120</b>, and an attachment position signal <b>135</b> from at least one attachment sensor <b>130</b>.

The boom sensor <b>120</b> (shown in <figref idref="DRAWINGS">FIG. 3</figref>) may be associated with the vertical pivoting motion of the attachment <b>100</b> imparted by hydraulic cylinders <b>340</b> (i.e. associated with the lifting and lowering motions of boom arms <b>150</b> relative to frame <b>50</b>). Specifically, the boom sensor <b>120</b> may be an angular position or speed sensor associated with a pivot joint between boom member <b>150</b> and frame <b>50</b>, a displacement sensor associated with the hydraulic cylinders <b>340</b>, a local or global coordinate position or speed sensor associated with an any linkage member coupling the attachment <b>100</b> to frame <b>50</b> or the attachment itself, a displacement sensor associated with movement of an operator input device from the operator station <b>320</b>, or any other type of sensor known in the art that may generate a signal indicative of a pivoting position or speed of the boom <b>90</b> relative to the frame <b>50</b> of the work machine <b>10</b>.

The attachment sensor <b>130</b> may be associated with the pivoting for of the attachment imparted by hydraulic cylinder <b>280</b>. Specifically, that attachment sensor <b>130</b> may be a pressure sensor associated with one or more chambers within hydraulic cylinder <b>280</b>, a strain gauge associated with the pivot connections of the attachment, a load cell, or any other type of sensor known in the art that generates a signal indicative of a pivoting force and or position of the attachment <b>100</b> of the machine during a loading, carrying, and dumping operation of the work machine <b>10</b>.

Calculating an attachment elevational position <b>30</b> by the controller <b>140</b> may further comprise a recognition of the type of attachment <b>100</b>. The controller may configure the object responsive control system <b>20</b> of a work machine <b>10</b> including systems operable to control the operation of a plurality of different attachments, each attachment having a set of parameters associated therewith which affect the operation of at least some of the systems of the work machine. The object responsive control system <b>20</b> may recognize the particular attachment coupled to the work machine based upon either a signal generated by an attachment recognition system associated with the attachment (RFID, Bluetooth, etc.) when the attachment is coupled to the work machine <b>10</b>, or based upon operator selectable commands for selecting any one of a plurality of different sets of operating parameters based upon the particular attachment <b>100</b> coupled to the work machine <b>10</b>. Upon recognition, the controller may factor the dimensional parameters or geometry of the attachment when calculating the attachment elevational position <b>30</b> because the boom position signal <b>125</b> and the attachment position signal <b>135</b> may translate into a different attachment elevational position <b>30</b> based on the dimensional parameters of the attachment <b>100</b>. Additionally, the predetermined threshold where an object response may be triggered will also be different based on the dimensional parameters of the attachment <b>100</b>. For example, a bucket attachment comes in various configurations such as roll-out buckets, grapple buckets, snow blowing buckets, and rock buckets. Each bucket attachment may have different dimensional parameters wherein the elevational height between the bottom surface of the bucket to the geographic surface will be different for each respective bucket. Furthermore, typical use and function of the attachment <b>100</b> can also determine the attachment elevational position <b>30</b>.

The controller <b>140</b> may be further adapted to activate an object response upon calculating an attachment elevational position <b>30</b> above the predetermined threshold and receiving an object signal <b>40</b> from the object sensor <b>110</b>. The controller <b>140</b> may be further adapted to deactivate the object response <b>145</b> upon calculating an attachment elevational position <b>30</b> below the predetermined threshold. For example, when the work machine <b>10</b> returns to a loading position (shown in <figref idref="DRAWINGS">FIG. 1A</figref>) from a carrying position (shown in <figref idref="DRAWINGS">FIGS. 1B and 1C</figref>), any object response will become inactive as the attachment will “scoop up” any undesirable objects in the travel path <b>310</b> of the work machine <b>10</b>. Additionally, the ability for the object responsive control system <b>20</b> to activate an object response <b>145</b> upon sensing an undesirable object will be inactive when the controller <b>140</b> calculates a position below the predetermined threshold.

The object sensor may be a laser sensor, a radar sensor, an infrared sensor, an acoustic sensor, a light sensor, a color sensor, or a camera. The object sensor (<b>110</b>A <b>110</b>B and generically referred to as <b>110</b>) may be located in a first position <b>110</b>A on or near a front surface of the work machine, at an elevation height below the predetermined threshold. Positioning an object sensor <b>110</b> in this first position <b>110</b>A provides ease of detecting whether the attachment <b>100</b> is in a loading position or a carrying position. In one example, an object sensor <b>110</b> that is a camera may automatically detect the manufacturer's signature colors of the attachment when the attachment is positioned in the loading position (shown in <figref idref="DRAWINGS">FIG. 1A</figref>), and thereby in the camera's field of view and inhibit the system's ability to activate an object response <b>145</b>. The system <b>20</b> would then automatically be enabled to activate an object response once the attachment is moved out of the field of vision of the camera. Alternatively, the object sensor <b>110</b> may be located in a position <b>110</b>B on or near a front surface of the work machine, above the predetermined threshold. The object sensor <b>110</b>B may be further adapted for sensing the presence of an undesirable object from an operator's point of view through a windshield of the operator's station within a field of view of the windshield. The second position <b>110</b>B would provide an object response <b>145</b> when detecting an undesirable object, the moment the operator's field of view <b>300</b> is at least partially obstructed. The object sensor <b>110</b> may be coupled to an object recognition software on the controller <b>140</b> that further processes the object signal <b>40</b>, and validates the perceived sensed object as undesirable.

The object sensor <b>110</b> may be adapted to activate a secondary object signal upon sensing the undesirable object on the geographical surface in the travel path of the work machine and elevationally below the attachment <b>100</b> of the work machine <b>10</b> (i.e. directly below the attachment when the attachment is in a carrying position). The secondary object signal may activate a heightened object response as the undesirable object in the path of travel of the work machine nears the work machine and thereby becoming an immediate threat to the ground engaging supports <b>70</b> and/or frame <b>50</b>. This would signal the operator to manually respond or the work machine <b>10</b> may be in a mode to automatically create an object response (e.g. an automated hydraulic braking).

An object response <b>145</b> may be an audible alarm <b>350</b>, a visual indicator <b>360</b>, an automated reduction in propel speed of the work machine <b>370</b>, steering of the work machine <b>375</b>, or an automated electrohydraulic braking of the ground engaging supports <b>380</b>. These are a few examples where the object response is in either a manual mode where the operator is alerted and directs the work machine, or in automatic mode where the work machine automatically responds. For example, an object response is in manual mode when the object response is a visual indicator <b>360</b>. This visual indicator may include a projected visual display of the travel path onto the windshield where the sensed undesirable objects are highlighted. Alternatively, the projected visual display may only highlight sensed undesirable objects and align the highlighted objects with the operator's point of view so that the graphical elements projected on the windshield <b>330</b> overlap with the corresponding objects seen through the windshield. This form of a visual indicator allows for the operator to view the perceived danger without having to look away from the travel path <b>310</b>.

The aforementioned disclosed features object responsive control system advantageously provides a semi-autonomous capability for the work machine while substantially improving its safety and reducing potential damage to the work machine and/or its attachment.

<figref idref="DRAWINGS">FIG. 5</figref> illustrates a method for providing an object responsive control system <b>30</b> for a work machine <b>10</b> having a frame <b>50</b>, a longitudinal axis extending along the length of the frame <b>50</b>, ground engaging supports <b>70</b> to support the frame <b>50</b> on a geographic surface <b>80</b>; a prime mover mounted on the work machine <b>10</b> and drivingly coupled to the ground engaging supports; an operator station supported by the frame; a boom <b>90</b> pivotally coupled to the frame <b>50</b>; an attachment <b>100</b> pivotally coupled to the boom <b>90</b>; and the attachment extending in a direction transverse to the longitudinal axis of the work machine.

At step <b>410</b>, the method comprises propelling the work machine <b>10</b> in a travel path <b>310</b> on the geographic surface <b>80</b>. The prime mover (not shown) is mounted on the work machine where the prime mover is drivingly coupled to the ground engaging supports <b>70</b> through conventional means, such as mechanical fluid, or a hydrostatic transmission. The prime mover mobilizes the ground engaging supports <b>70</b> and propels the work machine <b>10</b> over the geographic surface <b>80</b>.

At step <b>420</b>, the method comprises sensing an undesirable object located on the geographic surface <b>80</b> in the travel path <b>310</b> of the work machine <b>10</b>. This will typically be done by an object sensor <b>110</b> located someone on a forward facing area of the work machine <b>10</b>. The object sensor <b>110</b> may be a laser sensor, a radar sensor, an infrared sensor, an acoustic sensor, a light sensor, a color sensor, or a camera.

At step <b>430</b>, the method comprises delivering an object signal <b>40</b> upon sensing the undesirable object on the geographic surface <b>80</b> in the travel path <b>310</b> of the work machine <b>10</b>. The object sensor <b>110</b> may deliver an object signal <b>40</b> to the controller <b>140</b>. The object sensor <b>110</b> may be coupled to an object recognition software on the controller <b>140</b> that further processes the object signal <b>40</b>, and validates the perceived object as undesirable.

At step <b>440</b>, the method comprises delivering a boom position signal <b>125</b>.

At step <b>450</b>, the method comprises delivering an attachment position signal <b>135</b>.

At step <b>460</b>, the method comprises calculating an attachment elevational position <b>30</b> based on the boom position signal <b>125</b> and the attachment position signal <b>135</b>.

At step <b>470</b>, the method determines whether the attachment position signal <b>135</b> is above a predetermined threshold.

At step <b>480</b>, if yes, then an object response mode is activated. An activated object response mode enable the object responsive control system <b>20</b> to enable an object response <b>145</b> upon sensing an undesirable object in the travel path <b>310</b> of the work machine. An object response <b>145</b> may be an audible alarm <b>350</b>, a visual indicator, an automated reduction in propel speed of the work machine <b>370</b>, steering of the work machine <b>375</b>, or an automated electrohydraulic braking of the ground engaging supports <b>380</b>.

At step <b>490</b>, if not, then an object response mode remains inactive, or becomes inactivated. Inactiveness of the object response mode, or deactivating the object response mode, inhibits an object response <b>145</b> upon the detection of an undesirable object in the travel path of the work machine; or shuts off the object sensor <b>110</b>; or inhibits delivery of the object signal <b>40</b> upon sensing an undesirable object.

One or more of the steps or operations in any of the methods, processes, or systems discussed herein may be omitted, repeated, or re-ordered and are within the scope of the present disclosure.

While the above describes example embodiments of the present disclosure, these descriptions should not be viewed in a restrictive or limiting sense. Rather, there are several variations and modifications which may be made without departing from the scope of the appended claims.